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Carlos R. VillaDirector of K-12 Programs
National High Magnetic Field Laboratory2018 NSTA Distinguished Informal Science Educator
This presentation will be available to download at:https://nationalmaglab.org/education/
FAST Annual ConferenceSt. Augustine, FLOctober 2019
The National High Magnetic Field Laboratory is supported by National Science Foundation through NSF/DMR-1644779 and the State of Florida.
https://nationalmaglab.org/education/
NHMFL Overview
→One of 7 high magnetic field labs in the world→Only one in western hemisphere→Largest and highest powered in the world
NHMFL Overview
• User laboratory• Over 1615 user visits (2016)• NSF & State of Florida funded• Research free to scientist
• Must share research
• Research in many fields (Not • just magnets!!)• Materials – Energy - Life
• Includes materials science, physics, engineering, chemistry, biology, biomedical, geochemistry, microscopy, etc…
Center for Integrating Research & Learning
• Educational component of NHMFL’s grant• RET programs (more on that later…)• K-12 education outreach• 6,000 students visited this school year• Professional development• Workshops and conferences• CIRL on Facebook
PresenterPresentation Notes
https://www.facebook.com/MaglabEducation/
Magnet Review
• Gauss• Measurement of magnetic
field• Named for Carl Friedrich
Gauss
• Tesla• Measurement of larger
magnetic fields• Named for Nikola Tesla• 10,000 Gauss = 1 Tesla
PresenterPresentation Notes
Some Magnetic Fields (In Tesla)
• Refrigerator magnet: • Earth’s magnetic field:• Person’s magnetic field:• Junkyard magnet:• MRI magnet:
.03 T
.000045 T3 x10-13 T1 T2-3 T
Some NHMFL Magnetic Fields• ICR magnet:
• Ion Cyclotron Resonance• 900 Mhz NMR
• Nuclear Magnetic Resonance• Typical resistive magnet• Split cell • World record water cooled DC magnet• Hybrid magnet (33 MW)
• Resistive and superconducting• Series Connected Hybrid (14 MW)
• 1.5 Ghz NMR• NHMFL pulse magnet
• Not continuous field
21 T*
21 T
20-40 T25 T*41.5 T*45 T*
35 T*
100.7 T**World Record
First Discoveries
• In Greece, 2000 BC• Magnes the shepherd
• In China, 400 BC• Feng shui• The south pointer
• In Rome, 50 AD• Pliny the Elder• Naturalist and researcher• “Magic” with healing
properties
1269: Petrus Peregrinus de Maricourt
• Epistola de magnete• Part 1 discusses the physical (not occult) properties of
magnets• Magnetic fields can act at a distance• Magnets can only act on other magnetic materials• Opposite poles attract and like poles repel• When suspended, north poles point North and south
poles point South.
• Part 2 discusses the use of magnets in devices• Wet and dry compass
1600: William Gilbert
• Published De Magnete• Earth is a magnet
• First critical research on magnets• Used lodestone• Dispelled superstitions
and myths
1820: Hans Christian Ørsted
• An electrical current can create a magnetic field
• Oersted set up lecture demonstration• Used battery to supply
current• Showed compass
needle deflecting near the wire
1820: André-Marie Ampère
• Moving electrical charges produce magnetic fields
• Simple experiment• Two straight wires with current passed through• Wires bowed toward or away
• Led to electromagnets
1824: William Sturgeon
• First electromagnet• Curved iron rod• Bare copper wire• Electricity• 18 total turns of wire
• Lifted 9 pounds• Magnet weighed 7
ounces
1827: Joseph Henry• Improved the electromagnet
• Larger iron rod• Copper wire
• Insulated with silk• Electricity
• An electromagnet using two electrodes attached to a battery, best to wind coils of wire in parallel
• But an electromagnet using with multiple batteries, should use only one single coil
PresenterPresentation Notes
1900: SuperconductorsRe
sista
nce
Temperature
Traditional Metal
Superconductor
Tc0 Kelvin
1957: BCS Theory• BCS: Bardeen, Cooper, Schreiffer• At low temperatures, some metals lose
resistance• Atoms nearly stationary
• Superconductivity results from the formation of Cooper pairs• Two electrons partnered• One follows the other
• Results in frictionlessflow of electrons
Resis
tanc
e
Temperature
Traditional Metal
SuperconductorTc0 Kelvin
Magnets
• All magnets have poles• North & South• Opposites attract; Like repels
• But not really: Magnetic monopole• 2014 discovery
• All magnets have magnetic fields• Magnetic field is a vector field
• Has direction and magnitude
PresenterPresentation Notes
Magnetic FieldsMagnets Repel Magnets Attract
Magnetic Fields
• Magnetic fields invisible to humans• Many animals can sense magnetism
• Sea turtles• Migratory birds• Sharks
• Rare animals can see magnetism• Robins• Orangutans• Family Canidae
• Wolves, foxes, coyotes, dogs
Magnetic Materials• 3 metals are naturally magnetic at room
temperature• Iron• Nickel• Cobalt
• Two more are magnetic at lower temperatures• Gadolinium (65 F and below)• Dysprosium (-301 F and below)
• One more magnetic at abnormal conditions• Ruthenium (In unnatural form)
• Many are magnetic as alloys• Rare-Earth
• Magnetite • Iron rich mineral
• Lodestone is magnetized piece of magnetite• Lodestone led to first compass
PresenterPresentation Notes
Permanent & Temporary Magnets• Permanent magnets: Almost always keep their field
• Fields can be lost• Curie point (Heat)• Electric current (Degauss)• Hitting it (Blunt force)
• Temporary magnets: Will keep magnetic field until tampered with• Examples: Paperclips, scissors, staples, thumb tacks, pins,
screwdrivers, refrigerator door, car doors, etc…• Anything that is magnetic, but will not keep its field
PresenterPresentation Notes
Atomic Theory
• Name atom comes from Atomos, Greek for Indestructible• But not really
• The atom is divisibleProtonNeutronElectron
PresenterPresentation Notes
Magnetism• Motion of charged particles creates magnetic fields• In most atoms, disorganized spins cancel out
• Magnetic domains: when electrons line up• Magnetic field is produced when all electrons spin the
same direction:• More electrons lined up: more magnetism N
S
Electricity and Magnetism
• The two are so closely related• Where there is electricity, there is a magnetic field
• When electrons flow, they line up (Ørsted)• Where there is a magnetic field, electricity can be
created (Faraday)• Magnetic flux can create movement of electrons
Creating Magnetism From Electricity
• Electricity is the flow of electrons• Electrons flow in same direction
• This alignment of electrons creates a magnetic field around the conductor• Similar to electrons lining up in a
permanent magnet• So every wire carrying electricity
has a weak magnetic field around it
• Coiling the wire concentrates the magnetic field inside the coil
Bitter Plates
Permanent Magnets
• Magnet Exploration• Self discovery activity• Group Effort• Communicate your
discovery• Share with the class
Cow Magnets
Permanent Magnet Activity
• Money is magnetic• Coins are copper-nickel alloy
(not magnetic)• Pennies are copper-plated
zinc (also not magnetic)• Dollars are printed with iron-
rich ink (magnetic!)
• Foreign Coins• Canadian, British, Brazilian,
Mexican (some)…
Iron in the Food
• Iron in cereal• NIB Magnet is a must• Total brand• Baby cookies (high in
iron)
• The Hook:• Blend a $1• Use a NIB magnet• Pull out the iron
Temporary Magnet Activities
• No rubbing necessary• Magnetism happens
almost instantly• They are magnets
• North and South• Attract and Repel
• Paper Clips remain magnetic• Until something tampers
with their field• Field could last years
Teeny Tiny Beach Magnets
• Hold a strong magnet over beach sand
• Iron will attract to the magnet• Excess sand will cling to
the magnet• Purify by spreading it on
a sheet of paper and passing the magnet over it
• Meteors are high in iron content
• Burn up in atmosphere• Waves wash them
ashore
The Zinging Magnets
• Magnets are magnetized short length
• Made of strong barium ferrite
• They attract but bounce upon impact and separate
• Process repeats with a little energy lost each time
• Pitch changes• Frequency increases• Amplitude decreases
The Magnetic Hedgehog
• Ferrofluids aka liquid magnets• Suspension of iron
nanoparticles
• Fluid adheres to magnetic field lines
• Incredibly attractive (BE CAREFUL)
PresenterPresentation Notes
Electromagnets Extensions:
• Right hand rule• Direction of field
• Poles (Winding direction)• Variables:
• Neatness• Number of winds• Wire gauge• Battery strength• Temperature• Precision
Literature
Stop Faking ItBill Robertson
Driving ForceJames D. Livingston
A Short History of Nearly Everything
Bill Bryson
The Nature of ScienceJames Trefil
Literature
Additional Resources
Research Experience for Teachers 2020
• 6 weeks in the summer
• $3600 stipend
• June 8th – July 17th
• What do you have to do?• Complete online
application• Complete program
surveys and submit all research data
• Send in supporting documents (letter of rec, etc.)
Research Experience for Teachers 2018
What does RET entail? • Real world science:• Superconductivity
materials testing• Electricity & magnetism
research• Designing/constructing
research instruments• Running samples in
Electron Paramagnetic Resonance (EPR) or Nuclear Magnetic Resonance (NMR)
RET Logistics and Arrangements
• Housing• Stipend• Travel • Program is open to
Elementary, Middle, and High School teachers
• Pre-service teacher positions available
• Focus of the program• Nature of Science• Inquiry• Communicating in
science• Experimental Design
• Topics for research• Superconductivity• Electron Scanning
Microscopy• Condensed Matter
Before I Forget
• Business cards• Please do not hesitate to contact us with
questions, ideas, suggestions, etc…
• RET applications:• https://nationalmaglab.org/education/
https://nationalmaglab.org/education/teachers/professional-development/research-experiences-for-teachers
This is a Sub-title
Thank You
Carlos R. VillaDirector of K-12 Programs
[email protected] • 850-644-7191
mailto:[email protected]
Magnets and TheAbout UsSlide Number 3NHMFL OverviewCenter for Integrating Research & LearningAbout MagnetsMagnet ReviewSome Magnetic Fields (In Tesla)Some NHMFL Magnetic FieldsThe History �of MagnetsFirst Discoveries1269: Petrus Peregrinus de Maricourt1600: William Gilbert1820: Hans Christian Ørsted1820: André-Marie Ampère1824: William Sturgeon1827: Joseph Henry1900: Superconductors1957: BCS TheoryThe Science�of MagnetismMagnetsMagnetic FieldsMagnetic FieldsMagnetic MaterialsPermanent & Temporary MagnetsAtomic TheoryMagnetismElectricity and MagnetismCreating Magnetism From ElectricityBitter PlatesMagnetism Activities�For Your ClassroomPermanent MagnetsCow MagnetsSlide Number 34Iron in the FoodTemporary Magnet ActivitiesTeeny Tiny Beach MagnetsThe Zinging MagnetsThe Magnetic HedgehogElectromagnets Extensions:LiteratureSlide Number 42Additional ResourcesResearch Experience for Teachers 2020Research Experience for Teachers 2018RET Logistics and ArrangementsBefore I ForgetSlide Number 48